001/* 002 * Copyright 2021 Global Biodiversity Information Facility (GBIF) 003 * 004 * Licensed under the Apache License, Version 2.0 (the "License"); 005 * you may not use this file except in compliance with the License. 006 * You may obtain a copy of the License at 007 * 008 * http://www.apache.org/licenses/LICENSE-2.0 009 * 010 * Unless required by applicable law or agreed to in writing, software 011 * distributed under the License is distributed on an "AS IS" BASIS, 012 * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied. 013 * See the License for the specific language governing permissions and 014 * limitations under the License. 015 */ 016package org.gbif.utils.file; 017 018import java.io.ByteArrayOutputStream; 019import java.io.IOException; 020import java.io.InputStream; 021import java.io.UnsupportedEncodingException; 022import java.net.URL; 023import java.nio.charset.Charset; 024import java.nio.charset.StandardCharsets; 025 026import org.slf4j.Logger; 027import org.slf4j.LoggerFactory; 028 029public class InputStreamUtils { 030 031 private static final Logger LOG = LoggerFactory.getLogger(InputStreamUtils.class); 032 033 public InputStream classpathStream(String path) { 034 InputStream in = null; 035 // relative path. Use classpath instead 036 URL url = getClass().getClassLoader().getResource(path); 037 if (url != null) { 038 try { 039 in = url.openStream(); 040 } catch (IOException e) { 041 LOG.warn("Cant open classpath input stream " + path, e); 042 } 043 } 044 return in; 045 } 046 047 /** 048 * Converts an entire InputStream to a single String with UTF8 as the character encoding. 049 * 050 * @param source source input stream to convert 051 * 052 * @return the string representing the entire input stream 053 */ 054 public String readEntireStream(InputStream source) { 055 return readEntireStream(source, FileUtils.UTF8); 056 } 057 058 /** 059 * Converts an entire InputStream to a single String with explicitly provided character encoding. 060 * 061 * @param source source input stream to convert 062 * @param encoding the stream's character encoding 063 * 064 * @return the string representing the entire input stream 065 */ 066 public String readEntireStream(InputStream source, String encoding) { 067 if (!Charset.isSupported(encoding)) { 068 throw new IllegalArgumentException("Unsupported encoding " + encoding); 069 }; 070 071 ByteArrayOutputStream result = new ByteArrayOutputStream(); 072 073 try { 074 byte[] buffer = new byte[1024]; 075 int length; 076 while ((length = source.read(buffer)) != -1) { 077 result.write(buffer, 0, length); 078 } 079 } catch (IOException e) { 080 LOG.error("Caught exception", e); 081 } finally { 082 try { 083 source.close(); 084 } catch (IOException e) { 085 LOG.error("Caught exception", e); 086 } 087 } 088 089 // StandardCharsets.UTF_8.name() > JDK 7 090 try { 091 return result.toString(StandardCharsets.UTF_8.name()); 092 } catch (UnsupportedEncodingException e) { 093 throw new IllegalArgumentException("Could not decode stream as " + encoding); 094 } 095 } 096}